For many years, precious and non-precious gemstones have been mounted by crimping the gemstone between the prongs of a support structure, generally of metal, around and/or about the stone. Generally, the frame forming the setting, as well as the prongs of the support, remain visible when the jewel is viewed from above.
This manner of mounting may be suitable for stones of larger size, which are generally mounted as a single stone or with only a few stones. On the other hand, when it is desired to obtain a relatively large surface by placing smaller stones together, the visible metal parts create interruptions in the continuity of the surface. As a result, the visible metal parts detract from the aesthetic properties of the item and, therefore, are not always desirable.
To "invisibly" mount a large number of stones over a relatively large surface, the approach of the prior art has been to notch the diamonds and to mount them in a setting having two or more parallel walls, with metallic projections, e.g. prongs or the like, protruding from these walls for engaging notches in the gemstone. Typically, these walls define channels in which the stones are set, abutting one another in accordance with the known invisible mounting method.
Using the approach of the prior art, several problems and disadvantages arise. First, because of manufacturing variations in forming the notches and prongs to obtain a large matrix of stones, the fit between as least some of the stones and the walls may be imperfect. As a result, there may be too much play between the prongs and many of the stones and, therefore, a propensity of these loosely fitted stones to become dislodged. Therefore, there is a need in the jewelry industry for a variable gemstone setting which securely fixes stones of various and/or imperfect sizes within the setting without the risk of the stones becoming dislodged.
In addition, particularly in the case of a ring, a problem arises in that, in accordance with the teachings of the prior art, the walls which form the channels of the setting extend laterally, i.e. transversely to the major plane of the ring. Further, the metallic projections which are formed on the channel walls are fixed in place such that they do not exhibit a force upon and against the surface of the stones. As a result, when the wearer/manufacturer desires to adjust the size of the ring, particularly to downsize the ring to fit a thinner finger, decreasing the diameter of the ring has the effect of causing the lateral walls of the channels to move further apart. This loosens the inter-engagement between the metallic projections on the walls of the setting and the notches of the stones. As a result, previously well secured diamonds may fall out or become prone to be easily dislodged from the setting when the size of a ring is adjusted. Thus, rings designed using the teachings of the prior art can not readily be sized to fit the fingers of various users. Thus, a need exists in the marketplace for a gemstone setting which firmly locks gemstones in place such that, when used in conjunction with a ring, the ring may be effectively sized without loosing or dislodging the gemstones from within the gemstone.
Gemstone settings which include a plurality of gemstones, in which the setting is substantially invisible, are well known. For example Ramot (U.S. Pat. No. 5,123,265) discloses a gemstone assembly which includes a base formed with a plurality of ribs, defining at least one socket of rectangular configuration. Ribs of the setting are bent at their outer ends into grooves formed in the gemstone to fix the gemstone within the socket. However, Ramot does not disclose a slot cut within a bar of the setting, defining a flexible forward and rearward arm for securing gemstones in an invisible setting. Further, Ramot does not disclose a forward and rearward arm exerting a springing force upon the gemstone, thereby locking such stone firmly into the setting.
Another example is Muller (U.S. Pat. No. 5,419,159). Muller discloses an article of jewelry having a stone mounted on a support. The stone has two grooves formed on opposite sides of the stone to engage the support. The support is formed by a series of individual and separate bars, each bar having means for attachment to a neighboring bar. The attachment means permits pivoting of each bar with respect to the adjacent one. Each of the bars is dimensioned to receive stones along its length and each bar has a central recess of general V-shape which is open towards the top. However, Muller does not disclose a slot cut within the central bar along its length defining a flexible forward and rearward arm for securing a gemstone in an invisible gemstone setting. Further, in Muller the stones are not locked in place due to the pressurized springing force exerted by the forward and rearward arm upon the gemstone in the gemstone setting. Finally, Muller does not disclose a wire run through a hole along the entire length of the bar to increase the outward lateral force of the forward and rearward arm upon the gemstone, thereby clamping the stone within the setting.
Gem settings of widely varying structures, formed of more or less intricately shaped holding parts, are widely known in the jewelry industry. Setting stones within the structures generally requires substantial skill on the part of the jeweler, rendering the setting process both time consuming and expensive. This process becomes even more difficult and costly when fixing gemstones in "invisible" gemstone settings.
The conventional method of assembling a jewelry item with an invisible gemstone setting requires many difficult and intricate steps in order to place each individual gemstone correctly within the setting. These steps are repeated for all the rows or columns until the jewelry item is completed. This conventional method of invisibly setting gemstones to create jewelry items suffers from a number of disadvantages. First, casting of a jewelry item with a gemstone region including a recess and walls and preparing T-shaped cross bars is a relatively difficult and costly process. Such settings must be prepared in direct relation to the desired gemstone size such that any variation in size of the gemstone requires the casting of a corresponding setting. Further, slight inaccuracy or imperfection in the size of the gemstones will result in the inability to properly fix the gemstone within the specially designed setting. Thus, extra expense must be taken to insure precision and accuracy of both the pre-cut gemstones and the corresponding setting. Second, the assembly of the jewelry items requires considerable time of a skilled worker which adds greatly to the overall cost of the jewelry item. Lastly, the finished jewelry item cannot be readily downsized without disturbing the invisible gemstone setting.
Therefore, there is a need for a novel invisible gemstone setting which overcomes the disadvantages of the conventional prior art gemstone jewelry setting items. Furthermore, there is a need for a mass production technique of assembling jewelry items with invisible gemstone settings, so as to reduce the high cost of labor in the assembly of such jewelry items.